An aviation flight planning system is used for predicting and warning for intersection of flight paths with transported meteorological disturbances, such as transported turbulence and related phenomena. Sensed data and transmitted data provide real time and forecast data related to meteorological conditions. Data modelling transported meteorological disturbances are applied to the received transmitted data and the sensed data to use the data modelling transported meteorological disturbances to correlate the sensed data and received transmitted data. The correlation is used to identify transported meteorological disturbances source characteristics, and identify predicted transported meteorological disturbances trajectories from source to intersection with flight path in space and time. The correlated data are provided to a visualization system that projects coordinates of a point of interest (POI) in a selected point of view (POV) to displays the flight track and the predicted transported meteorological disturbances warnings for the flight crew.
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10. A method for predicting and warning of intersection of flight paths with transported meteorological disturbances comprising transported turbulence and related phenomena, and accounting for source characteristics, transport mechanism and modification of hazard during transport, and identification of the point of intersection with an aircraft flight path, the method comprising:
sensing data from sensing equipment on board the aircraft providing real time sensed information related to meteorological conditions, and receiving transmitted data providing real time and forecast data related to meteorological conditions;
storing flight plan information;
using a transported meteorological disturbances model to provide data modelling transported meteorological disturbances along the flight path indicated by the flight plan information;
analyzing the sensed data and the transmitted data using the data modelling transported meteorological disturbances to correlate the sensed data and transmitted data to identify transported meteorological disturbances source characteristics, identify predicted transported meteorological disturbances trajectories from source to intersection with flight path in space and time and communicate relevant aspects of the predicted transported meteorological disturbances trajectories; and
providing visualization of the analyzed data by:
acquiring at least one flight track as a focus object;
acquiring at least one transported turbulence prediction as a focus object;
using focus object information to display the focus objects;
subdividing each focus object into a plurality of object components;
using a transparent interface to calculate coordinates of components of the focus object in a coordinate system of the visualization system, said focus object mutually shared by the visualization system and the interface;
receiving coordinates of a point of interest in a projection of the visualization system;
projecting the point of interest (POI) in a selected point of view (POV) using the calculated coordinates and the received coordinates of the point of interest in the projection of the visualization system of N-dimensional features in the visualization, independent of user point of view; and
displaying the flight track and the relevant aspects of the predicted transported meteorological disturbances trajectories as warnings for the flight crew.
1. An aviation flight planning system for predicting and warning for intersection of flight paths with transported meteorological disturbances comprising transported turbulence and related phenomena, comprising:
a coordinating computer located on board an aircraft receiving sensed data from sensing equipment on board the aircraft providing real time sensed information related to meteorological conditions, and transmitted data received on board the aircraft, providing real time and forecast data related to meteorological conditions;
a flight plan information store communicatively connected to the coordinating computer;
a transported meteorological disturbances model store providing the coordinating computer with data modelling transported meteorological disturbances, with the received transmitted data and the sensed data to use the data modelling transported meteorological disturbances to correlate the sensed data and received transmitted data to identify transported meteorological disturbances source characteristics, identify predicted transported meteorological disturbances trajectories from source to intersection with a flight path indicated by the flight plan in space and time and communicate relevant aspects of the predicted transported meteorological disturbances trajectories;
communications to return observations from flight deck for verification and analysis; and
a visualization system configured to:
acquire at least one flight track as a focus object;
acquire at least one transported turbulence prediction as a focus object;
use focus object information to display at least a plurality of the focus objects;
subdivide each focus object into a plurality of object components;
use a transparent interface to calculate coordinates of components of the focus object in a coordinate system of the visualization system, said focus object mutually shared by the visualization system and the interface;
receive coordinates of a point of interest (POI) in a projection of the visualization system;
project the POI in a selected point of view (POV) using the calculated coordinates and the received coordinates of the POI in the projection of the visualization system of N-dimensional features in the visualization, independent of user point of view; and
display the flight track and the relevant aspects of the predicted transported meteorological disturbances trajectories as warnings for the flight crew.
2. The aviation flight planning system according to
3. The aviation flight planning system according to
4. The aviation flight planning system according to
5. The aviation flight planning system according to
6. The aviation flight planning system according to
the visualization system presents information about the focus objects with or without user interaction; and
the visualization system displays the relevant aspects of the predicted transported meteorological disturbances trajectories as warnings for the flight crew without user interaction and automatically generates an alert upon detection of an intersection of the flight track with transported turbulence within a predetermined time period.
7. The aviation flight planning system according to
8. The aviation flight planning system according to
9. The aviation flight planning system according to
11. The method according to
12. The method according to
13. The method according to
14. The method according to
15. The method according to
16. The method according to
17. The method according to
18. The method according to
presenting information about the focus objects with or without user interaction; and
displaying the relevant aspects of the predicted transported meteorological disturbances trajectories as warnings for the flight crew without user interaction and automatically generates an alert upon detection of an intersection of the flight track with transported turbulence within a predetermined time period.
19. The method according to
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The present patent application claims priority to Provisional Patent Application No. 62/175,659 filed Jun. 15, 2015, and No. 62/180,447 filed Jun. 16, 2015, which are incorporated by reference herein.
This invention was made with Government support under contract NNX15CA60P awarded by NASA. The Government has certain rights in the invention.
Field
The present disclosure relates to generation and display of weather and related information for flight planning. In particular, the present disclosure relates to prediction of the intersection of flight paths with transported meteorological disturbances.
Background
The technique described herein addresses Clear Air Turbulence (CAT) events which are not identified by current CAT prediction formalisms and/or commercial CAT prediction products, and which events are a cause of significant damage and injury encountered during long-haul commercial flights over remote oceanic areas. Such events are not uncommon, and occur in areas that are free of clouds, and are not located near jet stream or upper frontal shear zones associated with the Ellrod-Knox formalism, and are at large distances from possible “near-cloud” turbulence associated with convective storms. Similar considerations apply to the intersection of flight paths with other forms of transported meteorological disturbances and related phenomena, which may comprise volcanic gases and aerosols, radionuclide plumes, and tracers deliberately inserted to simulate a hazard source.
“Clear Air”, as used herein, means not in-cloud (satellite methods) and/or without precipitation (radar methods). “Clear air” is a negative recursive term, in that it references conditions other than conditions that are considered to be “Clear Air” encounters.
An aviation flight planning system is used for predicting and warning for intersection of flight paths with transported meteorological disturbances, which may comprise transported turbulence and related phenomena. A coordinating computer located on board an aircraft receives sensed data from sensing equipment on board the aircraft providing real time sensed information related to meteorological conditions, and transmitted data received on board the aircraft, providing real time and forecast data related to meteorological conditions. The sensed and received data are stored in a flight plan information store. A transported meteorological disturbances model provides data modelling transported meteorological disturbances and the model is applied to the received transmitted data and the sensed data to use the data modelling transported meteorological disturbances to correlate the sensed data and received transmitted data. The correlation is used to identify transported meteorological disturbances source characteristics, identify predicted transported meteorological disturbances trajectories from source to intersection with flight path in space and time and communicate relevant aspects of the predicted transported meteorological disturbance trajectories. The correlated data are provided to a visualization system for observations from flight deck for verification and analysis.
The visualization system is used to acquire at least one flight track as a focus object, acquire at least one transported turbulence prediction as a focus object, use focus object information to display the focus object, subdivide each focus object into a plurality of object components, and use a transparent interface to calculate coordinates of components of the focus object in a coordinate system of the visualization system. The focus object is mutually shared by the visualization system and the transparent interface to provide a visual indication of the transported meteorological disturbances. The visualization system receives coordinates of a point of interest (POI) in a projection of the visualization system, and projects the POI in a selected point of view (POV) using the calculated coordinates and the received coordinates of the POI in the projection of the visualization system of N dimensional features in the visualization, independent of user point of view, and displays the flight track and the relevant aspects of the predicted transported meteorological disturbances as warnings for the flight crew.
The file of this patent contains at least one drawing executed in color. Copies of this patent with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.
Overview
A Transported Turbulence Product (TTP) is described which follows the forensic analysis procedures currently used to evaluate potential causes for such encounters during Clear Air Turbulence (CAT) incident investigations. By performing the forensic analysis ahead of time, dispatchers can use flight plan intersections with predicted transported turbulence prediction regions to warn pilots prior to entry into high probability areas for such Transported Turbulence. Timely warnings will allow for either avoidance of, or for material and personnel in the cabin to be secured during, transit of the high probability areas for transported turbulence. These warnings can be integrated with cockpit displays and with inflight Electronic Flight Bag (EFB) equipment for cockpit use as now allowed by US Federal Aviation Administration (FAA) regulations.
The technique described is useful to general and commercial aviation, and to scientific personnel for Flight Operations during field experiments, especially for topics involving the tracking and detection of atmospheric trace constituents. The transported turbulence prediction technique employs advection of hazard-related tracers with warning times on the order of hours, and therefore extends the value of dated satellite and other remote observational data (hours since collection) without the requirement for real time data delivery. The transported turbulence predictions are delivered in Open Geospatial Consortium (OGC) formats which allow immediate import into most geobrowser based Common Operating Environment (COE) and Geographic Information System (GIS) visualization systems. Virtual Globe systems and applications extend the utility of transported turbulence prediction to other atmospheric hazards including volcanic aerosols and radionuclides, and are therefore ideal for the assembly and analysis of field experiment data on both terrestrial and extra-terrestrial globes.
While pilots and piloted aircraft are described, it is understood that the techniques can be used for flight decks and aircraft control facilities for other aircraft, such as, by way of non-limiting examples, manned, remote piloted vehicles, and automated unmanned systems.
The techniques described herein provide user tracking of long-range air transport and plume evolution and are useful to Dispatch and EFB Class 1 (unattached, e.g., handheld), Class 2 (mounted) and Class 3 (installed flight equipment subject to airworthiness requirements) applications, both on the ground and in flight. The Common Operating Environment (COE) approach reduces error of interpretation and user workload both on the ground and in the cockpit, which is especially important for icing hazard avoidance during Extended Operations (STOPS) (FAA requirement for alternate landing sites in event of depressurization or engine failure). Based upon benefits demonstrated at Hawaiian Airlines, any reductions in injury and/or improvements in airline performance will help reduce operations and insurance costs, and will see expanded use in the international commercial air transport industry.
Prediction is made of unanticipated Clear Air Turbulence (CAT) which is related to turbulence precursors injected upstream and transported over long ranges to the location of the CAT events and other transported meteorological disturbances other than visible precipitation. The transported CAT events are not identified by current CAT prediction formalisms and cause significant damage and injury when encountered during long-haul flights over oceanic areas. Such events are not uncommon and occur in areas that are free of clouds, are not located near the jet stream or upper frontal shear zones associated with the Ellrod-Knox formalism describing the Ellrod-Knapp turbulence index (TI) for CAT. It has been found that there are at large distances between some CAT events from possible “near-cloud” turbulence associated with convective storms.
In addition to CAT, the transported meteorological disturbances can comprise related phenomena having similar transport characteristics to transported turbulence. Non-limiting examples of such transported meteorological disturbances comprise volcanic gases and aerosols, radionuclide plumes, and tracers deliberately inserted to simulate a hazard source.
A Transported Turbulence Product (TTP) is produced for use by dispatch personnel in a commercial airline setting, and has been tested at Hawaiian Airlines during long-haul flights over the Pacific Ocean. The transported turbulence prediction and display product provides a combined interactive display of transported turbulence prediction renderings of volumetric positions with planned flight paths in a 4-dimensional visualization. This visualization allows rapid recognition of intersections or collocation in space and time as dispatchers or other users control time as a variable. It has been found that dispatchers can warn pilots prior to entry into high probability areas for transported turbulence, in which the warnings allow material and personnel in the cabin to be secured during transit. In addition to reducing damage and injury, transported turbulence prediction warnings can potentially lower carrier operating costs by reducing insurance premiums. The technique can also address warnings and avoidance of volcanic aerosol plumes and radionuclide layers.
An analysis of the NTSB data base from 1995 through 2014 reveals 219 accidents/incidents involving turbulence and large commercial jets (Part 121 class).
TT=transported turbulence,
NCT=near-cloud turbulence, and
IFIC=inadvertent flight into convection.
Most turbulence events resulted in serious injuries to one or more flight attendants or passengers. “Foreign” (non US jurisdiction) cases were not included in an analysis as there was insufficient information on them. Of the 219 accidents/incidents, 180 were weather-related. 92 of those were attributed in some way to convective activity, or about 51% of the total. The breakdown within the convective category was as follows:
Inadvertent flight into convection (IFIC)
55 (60%)
Near-cloud turbulence (NCT)
31 (33%)
Transported turbulence (TT)
6 (7%)
It is sometimes difficult to distinguish IFIC from NCT, even with good radar and satellite data. Many of the NCT case narratives have some clues to make the conclusion of IFIC, such as a storm cell that grew rapidly just ahead of the aircraft along the flight path, and which was not detected by radar. For transported turbulence cases (shown in Table 1), the crews usually testified that they were in the clear, in cirrus, and/or did not see any echoes on radar or visually within at least 10 miles:
TABLE 1
Transported Turbulence Events from the NTSB Accident Database
Altitude
Lag
Event Date
Time
(FL)
Location
Make/Model
Carrier
(hr)
1
Dec. 3, 2010
1042
180
Pago Pago
Boeing 767
Hawaiian
1
UTC
2
May 16, 2009
1545
350
Cuba (MWCR)
Boeing 757
Delta
3
UTC
3
Apr. 25, 2007
2335
130
LaPlata, MD
Boeing 737
Southwest
<1
UTC
4
Apr. 29, 2005
1231
410
Little Rock, AR
Boeing 737
Southwest
2
UTC
5
Jul. 25, 2004
0515
370
18.5N 75.2W
Boeing 777
American
5
UTC
E of Jamaica
6
Jul. 8, 1999
1810
290
180S Bermuda
Boeing 737
Continental
3
UTC
In four of the six transported turbulence cases, lag (or lead) time between storm development and projected turbulence arrival at the aircraft locations varied from 2 to 5 hours. Thus, warnings could have been issued to the aircraft to alert them to possible severe turbulence based on advection of the turbulence using upper air wind data from numerical prediction models, rawinsonde profiles, or satellite cloud motion vectors. The warnings (if relayed in a timely fashion via satellite uplink) would have been reliable, possibly preventing the injuries that occurred. In the other two cases, the lead time was probably too short (≦1 hr) to have allowed timely advisories to the flight crews.
Therefore, it is possible that roughly 5% of severe turbulence encounters could be related to transported turbulence. This is similar to the results of an analysis by Lane, et al. (Lane, T. P., R. Sharman, S. Trier, R. Fovell, and J. Williams, Recent advances in the understanding of near-cloud turbulence. Bull. Amer. Meteor. Soc., 499-515, 2012) using EDR data from commercial jet airliners that found the risk of convectively induced moderate to severe turbulence at 30 km or more to be 4% or less. This value is still well above the background risk (0.03%) for all sources of turbulence in the EDR database. Thus, it should not be unexpected that moderate to severe turbulence at longer distances, even greater than 100 km, from convective storms could occur.
Other weather-related causes for the incidents were: CAT 76 (42%), wake turbulence 8 (4%), icing 2 (1%) and cross winds 2 (1%). A few of the CAT cases were along the cirrus boundaries of mesoscale convective systems but quite far from the heavy radar echoes.
Example of a Transported Turbulence Warning Situation—Eastern Cuba
In one non-limiting example, on Jul. 25, 2004, a Boeing-777 airliner enroute from Miami to Sao Paulo, Brazil encountered brief “clear air turbulence” between eastern Cuba and Jamaica at Flight Level 370 around 0515 UTC, resulting in serious injury to a flight attendant. The vertical acceleration obtained from the Flight Data Recorder was a maximum of +1.6 g, which classifies it as severe turbulence. In
Example of a Transported Turbulence Warning Situation—Vanuatu CAT Event
Transported turbulence prediction is an estimation of a Transported Turbulence Product (TTP), which is based on transported turbulence predictions occurring at particular locations at particular times. This is similar to other weather predictions, in that past and present events are used to predict a particular condition at a particular time. In the case of CAT, the actual turbulence is not directly detected except by PIREPs and occasionally extracted from weather balloon data. Potential unpredicted turbulence is depicted by cyan contours (left-most 4 contours, starting near the SON identification label box), and advection downwind of a TSTM event is depicted in magenta contours (right-most 3 contours, close to the BA identification label box). In the depiction, an A330 aircraft, inbound to Honolulu, encountered severe turbulence just NE of Vanuatu (SON VOR). Standard predictions for CAT indicated a smooth flight (green flight track). HYSPLIT isentropic trajectories (dots) suggest how advection can transport CAT or its precursors downwind at high altitudes.
In the depiction of
The NOMADS Keyhole Markup Language (KML) wind barb stacks are consistent with the Jeppesen TRB product, which is also derived from the Global Forecast System (GFS) model. In such cases the FAA and NTSB usually look for TSTM (thunderstorm) “blow off” which can sometimes be seen in satellite animations. A relatively small TSTM candidate is found upwind of the incident site but with a cirrus feature visible in the IR for approximately 3 hours (magenta contours in
Flight Intersection with Transported Turbulence
The depiction of
Dynamic Cockpit Display
Transported turbulence probability is rendered on a cockpit display, providing a dynamic rendering of the transported turbulence probability based on transported turbulence prediction predictions. The display allows the pilot to visualize the transported turbulence probability and take action to avoid CAT from transported turbulence prediction in the manner of avoiding visible conditions and conditions rendered by radar or other directly sensed data. In addition, since the rendered display is itself a model, data can be extracted from the rendered display to either report the sensed transported turbulence probability or, where permitted, change course to evade or deliberately intercept a region of transported turbulence probability.
A coordinating computer located on board an aircraft receives sensed data from sensing equipment on board the aircraft providing real time sensed information related to meteorological conditions, and receives transmitted data, which is received on board the aircraft. The sensed data and received data provide real time and forecast data related to meteorological conditions. A flight plan information store communicatively connected to the coordinating computer is used to store flight plan information. The flight plan store may be internal to the coordinating computer or may be provided externally, for example from an electronic flight bag (EFB) or other flight computer equipment used for flight planning. The coordinating computer also has a transported meteorological disturbances model store that provides the coordinating computer with data modelling transported meteorological disturbances. The coordinating computer uses the sensed and received data and the data modelling transported meteorological disturbances to correlate the sensed data and received transmitted data to identify transported meteorological disturbances source characteristics, identify predicted transported meteorological disturbances trajectories from source to intersection with flight path in space and time. The coordinating computer then communicates relevant aspects of the predicted transported meteorological disturbances trajectories.
The relevant aspects are communicated to a flight display so that the pilot or flight control and flight planning or navigation equipment may use the information for flight planning purposes, which may include en-route re-planning. The pilot or dispatcher is then able to verify and analyze the data, and flight planning can be effected to accommodate the expected transported meteorological disturbances, either by avoiding the disturbance or by appropriate precautions, such as securing passengers and loose items and adjusting penetration speed.
The flight display provides visualization for viewing the transported turbulence predictions. The projected flight track and transported turbulence predicted locations are presented by the visualization system as focus objects and the focus objects are configured to present information about the focus objects with or without user interaction. Each focus object is subdivided into plural object components. A transparent interface is used to calculate coordinates of components of the focus object in a coordinate system of the visualization system. Each focus object mutually shared by the visualization system and the interface. Coordinates of a point of interest (POI) identified by a user are received in a projection of the visualization system. The POI is projected in a selected point of view (POV) using the calculated coordinates and the received coordinates of the POI in the projection of the visualization system of N dimensional features in the visualization, independent of user point of view. The relevant aspects of the predicted transported meteorological disturbances trajectories are displayed and used as warnings for the flight crew. This process can proceed without user interaction and an alert can be automatically generated when an intersection of the flight track with transported turbulence is detected in the near future.
In addition to providing information for the flight crew, the system can archive data used to generate alerts and warnings along with pilot and instrument observations of hazard strength at the intersection of flight paths with transported meteorological disturbances or waypoints. This allows collection of data to characterize hazard behavior and frequency of occurrence and storing the data in a data store.
The identification of intersects with regions of transported turbulence is improved through the use of data layer animation within the 4D geobrowser common operating environment (COE). The dispatcher or other user controls valid time to explore hazards which may appear along the flight path. Both the aircraft location and potential hazards are variable in space and time and follow their own trajectories. The displayed image changes in time and presents the dispatcher with the likely state of the atmospheric hazard(s) at near future times and locations, and clearly shows when the aircraft and potential predicted hazard(s) are in close proximity. Sample displays demonstrating the collocation of actual transported turbulence with HA451 on 8 Dec. 2015 are provided in
In
The three frames of
As indicated above in connection with
The transported turbulence prediction probability estimation method is broken down into steps as follows:
Received Information
The transported turbulence probability is established and displayed at several heights, including levels at, above and below the flight path. Transported turbulence prediction probability shows areas where the flight may encounter the remnants of previous vertical mixing events. Transported turbulence prediction is provided as a function of altitude and position in a format that can be plotted on an EFB (with suitable display/processing capability), and is nominally tailored to match the flight arrival time along the flight path. Therefore a set of transported turbulence prediction KML or charts are provided that can be animated in time, so that the pilot/dispatcher can understand when the aircraft will transit such areas, and thereby how to avoid or achieve a transit.
The information basis for the above steps follow received information.
It will be understood that many additional changes in the details, materials, steps and arrangement of parts, which have been herein described and illustrated to explain the nature of the subject matter, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.
Shipley, Scott T., Spence, Mark D., Ellrod, Gary P.
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